test.pl

use Mojolicious::Lite;
use Mojo::Asset::File;
use Alien::SwaggerUI;
use File::Spec::Functions qw( catfile );

get '/docs/*path' => { path => 'index.html' }, sub {
    my ( $c ) = @_;
    # Redirect so that trailing / helps browser build URLs and
    # we have our spec loaded. Can't make its own route because
    # the trailing `/` is optional in Mojolicious's route
    if ( !$c->req->url->path->trailing_slash && $c->req->url->path eq '/docs' ) {
        $c->req->url->path->trailing_slash(1);
        $c->req->url->query( url => '/v3' );
        return $c->redirect_to( $c->req->url );
    }
    my $path = catfile( Alien::SwaggerUI->root_dir, $c->stash( 'path' ) );
    my $file = Mojo::Asset::File->new( path => $path );
    $c->reply->asset( $file );
};

app->start;